Kevin J. Bianchini

Symptom Validity Testing: A Critical Review

This paper provides a comprehensive review of the published literature on symptom validity tests (SVT) and, with the accompanying tables, serves as a reference to assist in their selection, interpretation, and defense. Because malingering is inherently an applied problem that frequently arises in a medico-legal context, the use of SVTs must meet certain standards. Thus, a number of methodological and theoretical weaknesses of SVT research which limit the use of SVTs as clinical tools and sources of evidence are highlighted. These criticisms incorporate recommendations which must be addressed if conclusions based on SVT data are to meet the increasingly rigorous standards for the admissibility of scientific evidence.

Detecting Malingering in Traumatic Brain Injury and Chronic Pain: A Comparison of Three Forced-Choice Symptom Validity Tests

Individual and joint malingering detection accuracy of the Portland Digit Recognition Test (PDRT), Test of Memory Malingering (TOMM), and Word Memory Test (WMT) was examined in traumatic brain injury (TBI; 43 non-malingering, 27 malingering) and chronic pain (CP; 42 non-malingering, 58 malingering) using a known-groups design. At published cutoffs, the PDRT and TOMM were very specific but failed to detect about 50% of malingerers; the WMT was sensitive but prone to false positive errors. ROC analyses demonstrated comparable accuracy across all three tests. Joint classification accuracy was superior to that of the individual tests. Clinical and research implications are discussed.

WAIS digit span-based indicators of malingered neurocognitive dysfunction: classification accuracy in traumatic brain injury.

The present study determined specificity and sensitivity to malingered neurocognitive dysfunction (MND) in traumatic brain injury (TBI) for several Wechsler Adult Intelligence Scale (WAIS) Digit Span scores. TBI patients (n = 344) were categorized into one of five groups: no incentive, incentive only, suspect, probable MND, and definite MND. Performance of 1,063 nonincentive patients (e.g., cerebrovascular accident, memory disorder) was also examined. Digit Span scores included reliable digit span, maximum span forward both trials correct, maximum span forward, combined maximum forward and backward span, Digit Span scaled score, maximum span backward both trials correct, and maximum span backward. In TBI, sensitivity to MND ranged from 15% to greater than 30% at specificities of 92% to 98%. Patient groups with documented brain pathology had higher false-positive error rates. These results replicate previous known-groups malingering studies and provide valuable data supporting the WAIS Digit Span scores in detection and diagnosis of malingering.

Detecting Malingered Neurocognitive Dysfunction Using the Reliable Digit Span in Traumatic Brain Injury

This study assessed the effectiveness of Greiffenstein’s Reliable Digit Span (RDS) score for the detection of malingered neurocognitive dysfunction. Participants were 54 traumatic brain injury patients referred for neuropsychological evaluation. Twenty-four met the Slick, Sherman, and Iverson criteria for at least probable malingered neurocognitive dysfunction. The control group was composed of 30 patients without external incentive and who thus did not meet the Slick criteria. All patients completed the digit span test as part of either the WAIS-R or WAIS-III. The RDS scores were calculated, and sensitivity, specificity, and predictive power were examined for several cutoffs. Classification accuracy for the RDS was excellent. Issues related to the clinical application of this technique are discussed.

Sensitivity and Specificity of MMPI-2 Validity Scales and Indicators to Malingered Neurocognitive Dysfunction in Traumatic Brain Injury

The present study used a known-groups design to determine the classification accuracy of 10 MMPI-2 validity scales and indicators in the detection of cognitive malingering in traumatic brain injury. Participants were 259 traumatic brain injury and 133 general clinical patients seen for neuropsychological evaluation. The TBI patients were subdivided into groups based on a comprehensive examination of effort following Slick, Sherman, and Iversons (1999) criteria. More extreme scores demonstrated excellent specificity; often impressive sensitivity was seen even while maintaining a low false positive error rate. Specificity was good even in stroke, memory disorder, and psychiatric patients without incentive. The results of this study are presented in frequency tables that can be easily referenced in clinical practice.

Classification Accuracy of the Test of Memory Malingering in Traumatic Brain Injury: Results of a Known-Groups Analysis

This study used a known-groups design to determine the classification accuracy of the Test of Memory Malingering (Tombaugh, 1996, 1997) in detecting cognitive malingering in traumatic brain injury (TBI). Forty-one of 161 TBI patients met Slick, Sherman, and Iverson (1999) criteria for Malingered Neurocognitive Dysfunction. Twenty-two no-incentive memory disorder patients were also included. The original cutoffs (<45) for Trial 2 and Retention demonstrated excellent specificity (less than a 5% false positive error rate) and impressive sensitivity (greater than 45%). However, these cutoffs are actually conservative in the context of mild TBI. Over 90% of the non-MND mild TBI sample scored 48 or higher on the Retention Trial and none scored less than 46 while 60% of the MND patients claiming mild TBI were detected at those levels. Trial 1 also demonstrated excellent classification accuracy. Application of these data to clinical practice is discussed.

Pain, Malingering, and Performance on the WAIS-III Processing Speed Index

Pain patients often report cognitive symptoms and many will include them in their claims of disability. The Processing Speed Index (PSI) of the WAIS-III was investigated as one aspect of cognitive functioning in six groups. Slight impairment was found for PSI and Digit Symbol subtest performance, but not for Symbol Search, in a Laboratory-induced Pain group and a Clinical Pain group. The lowest scores were found in a Simulator group instructed to fake cognitive impairment and a Clinical Pain group diagnosed as Malingering. Results suggest that PSI scores are only slightly reduced by laboratory-induced pain or chronic pain, and that unexpectedly low scores in the absence of significant/documented brain dysfunction suggest poor effort or deliberate misrepresentation.

Detecting malingered performance on the Wechsler Adult Intelligence Scale: Validation of Mittenberg's approach in traumatic brain injury

This study assesses the effectiveness of the Wechsler Adult Intelligence Scale (WAIS) performance validity markers devised by Mittenberg et al. [Prof. Psychol.: Res. Pract. 26 (1995) 491] in the detection of malingered neurocognitive dysfunction (MND). Subjects were 65 traumatic brain injury (TBI) patients referred for neuropsychological evaluation. Twenty-eight met the Slick et al. [Clin. Neuropsychol. 13 (1999) 545] criteria for at least probable MND. The control group was comprised of 37 patients without external incentive and who thus did not meet the Slick et al. criteria. All subjects completed the Wechsler Adult Intelligence Scale-Revised (WAIS-R or WAIS-III). The discriminant function score (DFS) and the vocabulary-digit span (VDS) difference score were calculated and sensitivity, specificity, and predictive power were examined for several cut-offs for each marker individually and the two combined. Classification accuracy for the DFS was acceptable and better than for VDS. The use of the two markers in combination resulted in no incremental increase in classification accuracy. Issues related to the clinical application of these techniques are discussed.

Detecting Malingered Performance With the Wisconsin Card Sorting Test: A Preliminary Investigation in Traumatic Brain Injury

The present study examined the classification accuracy of four potential Wisconsin Card Sorting Test malingering indicators (Bernard and Suhr formulas and two types of Unique responses). Participants were 89 traumatic brain-injury (TBI) patients assigned to malingering and nonmalingering groups on the basis of the Slick, Sherman, and Iversion (1999) criteria. Individual Sensitivities were greater than .33 with acceptable Specificity. Combined Sensitivity for two of the indicators was greater than .60. Overall, this study demonstrated three distinct approaches to the WCST used by probable malingerers. The clinical relevance of these findings and directions for future research are discussed.

California verbal learning test indicators of malingered neurocognitive dysfunction: sensitivity and specificity in traumatic brain injury

The present study used well-defined traumatic brain injury (TBI) and mixed neurological (other than TBI) and psychiatric samples to examine the specificity and sensitivity to Malingered Neurocognitive Dysfunction (MND) of four individual California Verbal Learning Test (CVLT) variables and eight composite CVLT malingering indicators. Participants were 275 traumatic brain injury and 352 general clinical patients seen for neuropsychological evaluation. The TBI patients were assigned to one of five groups using the Slick, Sherman, and Iverson (1999) criteria: no incentive, incentive only, suspect, and malingering (both Probable MNDand Definite MND). Within TBI, persons with the strongest evidence for malingering (Probable and Definite) had the most extreme scores. Good sensitivity (approximately 50%) in the context of excellent specificity (> 95%) was found in the TBI samples. Issues related to the appropriate clinical application of these data are discussed.